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91.
Food components influence the physiology by modulating gene expression and biochemical pathways within the human body. The disease-preventive roles of several fruit and vegetable components have been related to such properties. Polyphenolic components such as flavonoids are strong antioxidants and induce the expression of several xenobiotic-detoxifying enzymes. The mechanism of selective cytotoxicity induced by red grape wine polyphenols against MCF-7 breast cancer cells was investigated in relation to their interference with calcium homeostasis. MCF-7 cells showed an increase in cytosolic calcium levels within 10 min of treatment with the polyphenols. Immunohistochemical localization of calmodulin with secondary gold-labeled antibodies showed similar levels of gold labeling in both MCF-7 cells and the spontaneously immortalized, normal MCF-10A cell line. MCF-7 cells treated with the red wine polyphenol fraction (RWPF) showed swelling of endoplasmic reticulum, dissolution of the nucleus, and loss of plasma membrane integrity as well as reduced mitochondrial membrane potential. These cells were arrested at the G2/M interphase. By contrast, MCF-10A cells did not show such changes after RWPF treatment. The results suggest that polyphenol-induced calcium release may disrupt mitochondrial function and cause membrane damage, resulting in selective cytotoxicity toward MCF-7 cells. This property could further be developed toward breast cancer prevention strategies either independently or in conjunction with conventional prevention therapies where a positive drug-nutrient interaction can be demonstrated.  相似文献   
92.
OBJECTIVE: To determine the prevalence of obesity and body fat distribution of Moroccan women of childbearing age, using a panel of anthropometric measurements. DESIGN AND SETTING: A cross-sectional survey conducted in 1995 in an agricultural community, El Jadida province of Morocco. Weight, height, waist and hip circumferences and triceps, biceps, subscapular and supra-iliac skinfold thicknesses were measured. Body mass index (BMI), waist/hip ratio (WHR), sum of all and sum of trunk skinfold thicknesses were determined. SUBJECTS: In total, 1269 women aged 15-49 years from urban and rural areas were surveyed. RESULTS: The means of all anthropometric measurements including body fat were higher in urban than in rural women and increased with age. Trunk fat contributed 50% of total fat. Globally, 4.7% of women were underweight (BMI<18.5 kg m(-2)), 35.2% were overweight or obese (BMI> or =25 kg m(-2)), 10.1% were obese (BMI> or =30 kg m(-2)) and 16.8% had central obesity (WHR>0.85). The prevalence of overweight and obesity was higher in the urban than in the rural area. Underweight prevalence decreased with age, whereas that of overweight and obesity increased. All anthropometric parameters adjusted for age increased with the increase of BMI and WHR. CONCLUSIONS: Although undernutrition is still prevalent, there is an alarming prevalence of overweight and obesity in Moroccan women of childbearing age. The results indicate a shift in this country from the problem of dietary deficiency to the problem of dietary excess, and alert one to the necessity of establishing an intervention to prevent obesity-related diseases. It is necessary to address which of the anthropometric variables studied here is the best predictor of obesity-related diseases in this population.  相似文献   
93.
The communication describes standardization of an efficient in vitro propagation and hardening procedure for obtaining plantlets from field grown culms of Bambusa tulda. Administration for 10 min of 0.05 and 0.1% mercuric chloride to explants collected in winter and summer seasons, respectively facilitated optimum culture establishment and bud break. 0.1–0.2% mercuric chloride in rainy season enhanced aseptic culture establishment but inhibited bud break due to toxicity to explants. MS liquid medium enriched with 100 μM glutamine, 0.1 μM indole-3-acetic acid and 12 μM 6-benzylaminopurine supported maximum in vitro shoot multiplication rate of two-fold. The proliferated shoots were successfully rooted on MS liquid medium supplemented with 40 μM coumarin resulting in a maximum of 98% rooting. The procedure requires 45 days cycle for the in vitro clonal propagation (15 days for shoot multiplication and 30 days for root induction) and 80 days for acclimatized plantlet production.  相似文献   
94.
This study was carried out of 4,419 animals raised in an extensive system on local breed sheep of the Tiaret region during 2 years (2010–2011) to determine some clinical and pathological aspects associated to caseous lymphadenitis (CL). Clinical examination revealed a prevalence rate of 5.7 %. CL prevalence rate was significantly higher in females (6 %) than in males (4.8 %). The most affected superficial lymph nodes were mandibular lymph nodes (46.1 %). Gross examination of 1,679 carcasses of sheep at the abattoir revealed the presence of abscesses on 250 carcasses (14.9 %). Out of 105 cases showing lesions of CL, Corynebacterium pseudotuberculosis (53.6 %) was isolated as mixed infection with Staphylococcus aureus (43 %) and Escherechia coli (17.9 %). CL prevalence was significantly higher in adult than in young sheep and in female than in male ones. Visceral form of CL was associated to “thin ewe syndrome” responsible for significant economic losses in Algeria.  相似文献   
95.
Since the first successful nuclear transfer (NT) experiments were carried out, various somatic cell types have been used as donor cells for production of cloned animals. In most experiments, fibroblasts are used since they only need to be isolated and cultivated. Recently, some researchers have shown that different cell cultures from different sources possess different capacities to support preimplantation development of NT embryos. The blastocyst rates obtained in our previous studies varied and were as high as 45% in relation to the number of reconstructed embryos. This led us to question whether the origin and culture conditions of the defined male and female fibroblast lines could be responsible for the differences in developmental potency. Taking all our results into consideration, we conclude that different fibroblast lines recovered from the same tissue and cultivated under equal culture conditions could produce dramatically different blastocyst rates. The influence of cell line itself is higher than the influence of passage number. The observed effects of cell cycle stage, chromosomal aberrations, and diminished vitality are important but not sufficient to discriminate well-qualified nuclear donor cells. We speculate that some epigenetically regulated deviations in the gene expression program are responsible for these phenomena. Explanation of the underlying mechanisms should contribute to better understanding of epigenetic reprogramming and may ultimately assist reprogramming in the laboratory.  相似文献   
96.
Fisheries have had major negative impacts on marine ecosystems, and effective fisheries management and governance are needed to achieve sustainable fisheries, biodiversity conservation goals and thus good ecosystem status. To date, the IndiSeas programme (Indicators for the Seas) has focussed on assessing the ecological impacts of fishing at the ecosystem scale using ecological indicators. Here, we explore fisheries ‘Management Effectiveness’ and ‘Governance Quality’ and relate this to ecosystem health and status. We developed a dedicated expert survey, focused at the ecosystem level, with a series of questions addressing aspects of management and governance, from an ecosystem‐based perspective, using objective and evidence‐based criteria. The survey was completed by ecosystem experts (managers and scientists) and results analysed using ranking and multivariate methods. Results were further examined for selected ecosystems, using expert knowledge, to explore the overall findings in greater depth. Higher scores for ‘Management Effectiveness’ and ‘Governance Quality’ were significantly and positively related to ecosystems with better ecological status. Key factors that point to success in delivering fisheries and conservation objectives were as follows: the use of reference points for management, frequent review of stock assessments, whether Illegal, Unreported and Unregulated (IUU) catches were being accounted for and addressed, and the inclusion of stakeholders. Additionally, we found that the implementation of a long‐term management plan, including economic and social dimensions of fisheries in exploited ecosystems, was a key factor in successful, sustainable fisheries management. Our results support the thesis that good ecosystem‐based management and governance, sustainable fisheries and healthy ecosystems go together.  相似文献   
97.
Landscape Ecology - Place-based transdisciplinary research involves multiple academic disciplines and non-academic actors. Long-Term Socio-Ecological Research (LTSER) platform is one concept with ~...  相似文献   
98.
Fenugreek plant is susceptible to water stress during the vegetative growth stages, since a soil matric potential lower than –0.3 MPa causes substantial reduction in growth parameters such as height, weight and total leaf area. Gibberellic acid (GA3) application to the seeds before sowing caused slight changes in growth parameters as well as some physiological and biochemical aspects under water deficit conditions.Water stress decreased the area of leaves by reducing the number and volume of cells. Leaf growth was improved by GA3 treatment by promoting the growth processes slightly. Photosynthetic pigments (Chlorophyll a and b, and carotenoids) in the leaves diminished and the concentrations of the main cations (Na+, K+, Ca2+ and Mg2+) were disturbed by a decreasing soil matric potential. Monosaccharides accumulated markedly under water stress, and GA3 may have further stimulated such accumulation. A substantial reduction in total soluble nitrogen was accompanied by a marked increase in protein-N. The possible physiological and biochemical roles of such alterations in the chemical constituents are discussed. Received: 20 March 1998  相似文献   
99.
In the present study, arbuscular mycorrhizal fungi (AMF) (Glomus monosporus, Glomus deserticola, Glomus clarum and a complex of native AMF coming from the Aoufous date palm grove in the south of Morocco) have been shown to protect date palm seedlings against bayoud disease. Treatment with AMF reduced disease severity by 8–77% depending on the AMF isolate used. In addition, all mycorrhizal fungi stimulate significantly shoot height and biomass and increase the number of leaves per plant. The plants associated with Aoufous complex present the best improvement of plant growth and great effectiveness in reducing bayoud disease incidence. Moreover, the AMF induce change in activities of two defence-related enzymes (peroxidases and polyphenoloxidases). The potential involvement of this induced biochemical defence reaction in protecting date palm against bayoud is discussed.  相似文献   
100.
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